Pressure relief valve



Aug.23,'1938. gum 2,128,039

PRESSURE RELIEF VALVE Filed Aug. 22, 1936 Patented 23, 1938 PATENT OFFICE PRESSURE VALVE Alois Cibulka, Baytown, Tex, aslig nor to Stand-' ard Oil Development Company, a orporation of Delaware Application sum as, 1988, Serial No. 91391 lCla-i'm.

(Cl. lat-s3) This invention relates to improvements in A "floating" valve stem guide ll, having a automatic release devices of the frangible type for containers which may besubjected to excessive pressure. The principal object of the device is to provide a release device in which rupturing of the frangible element'will not prevent continued operation of the container under the normal pressure for which it is designed or adjusted. The invention will be fully understood 8 m from the following description, read in connection with the accompanying drawing in which Fig. l is a vertical section through the device. Fig. 2 is a transverse section on the line II--II looking up.

Fig. 3 is a transverse section on 'the line IIIIII looking down. Referring to the drawing numeral I denotes the outlet pipe or nozzle of a pressure vessel. Numeral 2 denotes an extension of said nozzle consisting of a pipe having an internal diameter greater than that of the nozzle I. Flanges I and 4 are provided on the respective ends of the pipes I and 2. Numeral 5 denotes a valve body preferably formed of a short section of pipe similar to that of the extension 2 and of substantially the same lateral dimensions. The valve body is flanged at both ends as indicated by numerals Ii and l and adapted for insertion between the ends of pipes I and I. 1 The flanges i and I are adapted to be joined by bolts or other suitable mea .and by reason of the diflference in internal diameter between the nozzle I and the valve body 5 an annular shoulder 8 is formed at the junction. In making the joint, a disc 9 or flat sealing member of frangible material, metal or fibrous, and preferably lead or copper or a combination of both, is inserted between the flanges 3 and 1 so as to seal the open end of the nozzle I and provide a fluid and vapor 0 tight union between the. nozzle and the valve body. The dotted lines indicate the position of the seal within the valve body after the seal has been ruptured and excess pressure released from the vessel. I 45 Disposed above or on the outer face of the sealing member Ilsa valve head II. This member is of such greater diameter than the nozzle I that the shoulder 8 provides a seat therefor with the member 8 interposed. In the outer or upper face of the valve head III is a centrally disposed cavity Ii adapted to receive the enlarged end I! of a valve stem. The walls of the cavity II and valve end 12 maybe threaded or otherwise provided for rigid engagement with one another. but it is pre- 55 ferred that they be freely associated.

central hub II, through which the valve stem extends, and spokes It extending radially outwardly into sliding relationship tothe wall of the valve body, bears upon the outer surface of the 5 enlarged portion I! of the valve stem. The hub I5 oithe valve guide I4 provides a seat for a valve spring ll encircling the valve stem.

A guide for the other end of the valve stem is provided by a hollow bolt I8 threaded for engage- 1 ment with the inner wall of an annular hub I8 on the spider 20. The spider 20 has an annular rim 2i adapted to be rigidly positioned between the flanged ends 6 and 4 oi the valve body'i and the extension pipe 2 respectively. Spokes 22 [5 Join the rim II to the hub It. An annular member 23 encircles the valve stem adjacent the outer end thereof and provides a seat for the outer end of the spring I1 and also a bearing member for the bolt I8 which may be turned inwardly or out- 20 wardly thru the spider hub I8 in order to vary the degree of pressure exerted by the spring I! on the valve head I0. The valve stem is free to move in or out of the peway in the bolt I8 as may be required by the operation of the 25 device.

. In operation, a sealing member 8 is used which will have a predetermined resistance to shear. This resistance need not necessarily be great as'it is supplemented by the pressure of the valve head so III as imparted by its weight and by the pressure exerted by the spring I1. Further adjustment of the resistance to pressures exerted against the inner side of the seal may be made by means of the adjusting bolt I8. Ordinarily the strengthof 35 the sealing member should be just suflicient to withstand the pressure difference between normal operating pressures and the maximum operating pressure, at which release is deemed necessary. The valve itself will ordinarily be adiusted to 40 compensate for that pressure under which normal operation will.take place.

When pressure against the under side of the sealing member exceeds the maximum operating pressure for which the valve has been adjusted,

- the member will shear circumferentially of the wall of the valve body, the free edge of the sealing member between the valve head and the wall being forced inward to form acap. for the head Itand form a deflector-to prevent direct contact with the valve parts of fluids flowing thru the valve at high velocity. The valve head of course will move upwardly against the tension of the ring "until the pressure in the vessel with whichthevalveisconnectedhasbeenrestoredto 56 that under which the vessel is normally operated and to which the valve spring has been adjusted. The valve head will then be forced back into position over the outlet nozzle opening with the sealing member functioning in the manner of a valve gasket to maintain svapor and fluid tight seal so long as the operations continue at normal pressure. The operation of the vessel may be continued without diiiiculty until it is convenient to replace the sealing member.

The foregoing description is illustrative only and various changes and alternative arrangements may be made within the scope oi the appended claim, in which it is my intention to claim all novelty inherent in the invention as broadly as the prior art permits.

I claim:

In a pressure relief device including a pressure hollow bolt.

inlet nozzle and an outlet pipe, a valve, comgreater than said nozzle; a frangible disc disposed between the adjacent ends of the casing and said nozzle; a valve head and stem within the casing,-

prising a casing having an internal diameter casing and spring means for loading said valve,

mounted between the spider within the casing and the hollow bolt and adjustable by means of said ALOIS CIBULKA. 

